Onsbjerg is an urban Settlement in Samsø Municipality, in the region of Central Denmark, Denmark. Onsbjerg lies at 11 m above sea level. It has 224 inhabitants (2026). The nearest city is Aarhus, 41 km to the northwest. Among the landmarks around are Ilse Made kilde (3.3 km), Vesborg (8.9 km) and Nils Halses Høj (3.8 km). Among the natural features are Dyret (0.9 km).
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